<template>
  <div class="cart">
    <h4>全部商品</h4>
    <div class="cart-main">
      <div class="cart-th">
        <div class="cart-th1">全部</div>
        <div class="cart-th2">商品</div>
        <div class="cart-th3">单价（元）</div>
        <div class="cart-th4">数量</div>
        <div class="cart-th5">小计（元）</div>
        <div class="cart-th6">操作</div>
      </div>
      <div class="cart-body">
        <ul class="cart-list" v-for="cart in cartInfoList" :key="cart.id">
          <li class="cart-list-con1">
            <input
              type="checkbox"
              name="chk_list"
              :checked="cart.isChecked == 1"
              @click="updateStateById(cart, $event)"
            />
          </li>
          <li class="cart-list-con2">
            <img :src="cart.imgUrl" />
            <div class="item-msg">{{ cart.skuName }}</div>
          </li>
          <li class="cart-list-con4">
            <span class="price">{{ cart.skuPrice }}</span>
          </li>
          <li class="cart-list-con5">
            <a class="mins" @click="handler('minus', -1, cart)">-</a>
            <input
              autocomplete="off"
              type="text"
              :value="cart.skuNum"
              @change="handler('change', $event.target.value * 1, cart)"
              minnum="1"
              class="itxt"
            />
            <a class="plus" @click="handler('add', 1, cart)">+</a>
          </li>
          <li class="cart-list-con6">
            <span class="sum">{{ cart.cartPrice * cart.skuNum }}</span>
          </li>
          <li class="cart-list-con7">
            <a class="sindelet" @click="deleteCartById(cart.skuId)">删除</a>
            <br />
            <a>移到收藏</a>
          </li>
        </ul>
      </div>
    </div>
    <div class="cart-tool">
      <div class="select-all">
        <input
          class="chooseAll"
          type="checkbox"
          :checked="isAllChecked && cartInfoList.length > 0"
          @click="updateAllCartChecked"
        />
        <span>全选</span>
      </div>
      <div class="option">
        <a @click="deleteAllCheckedCart">删除选中的商品</a>
        <a href="#none">移到我的关注</a>
        <a href="#none">清除下柜商品</a>
      </div>
      <div class="money-box">
        <div class="chosed">已选择 <span>{{getSelectedGoods}}</span>件商品</div>
        <div class="sumprice">
          <em>总价（不含运费） ：</em>
          <i class="summoney">{{ getTotalPrice }}</i>
        </div>
        <div class="sumbtn">
          <a class="sum-btn" @click="settle" target="_blank">结算</a>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
import { mapGetters } from "vuex";
//按需引入throttle 节流
import throttle from "lodash/throttle";
export default {
  name: "ShopCart",
  mounted() {
    this.$store.dispatch("getShopCart");
  },
  computed: {
    ...mapGetters(["cartList"]),
    cartInfoList() {
      return this.cartList.cartInfoList || [];
    },
    //获取当前选中的有多少件商品
    getSelectedGoods(){
      let selectGoods = this.cartInfoList.filter((_d) => _d.isChecked == "1");
      return selectGoods.reduce((_n, _c) => _n + 1, 0);
    },
    //获取总价
    getTotalPrice() {
      //filter传一个参数 匿名函数
      // 会放回原数组中满足条件的所有数组
      // let selectGoods = this.cartInfoList.filter(function(_d){
      //   return _d.isChecked == '1'
      // })
      // es6写法
      let selectGoods = this.cartInfoList.filter((_d) => _d.isChecked == "1");
      //reduce 两个参数，一个匿名函数，一个是累计的初始值
      //匿名函数也有两个参数，第一个是承接累计的值的中间值，第二个参数就是数组的每一个项
      // let sum = selectGoods.reduce(function (_n, _c) {
      //   return _n + _c.skuNum * _c.skuPrice;
      // }, 0);
      // es6
      let sum = selectGoods.reduce((_n, _c) => _n + _c.skuNum * _c.skuPrice, 0);
      return sum;
    },
    isAllChecked() {
      // every遍历的每一个都为真，结果才为真，有一个是false，结果都为false
      return this.cartInfoList.every((item) => item.isChecked == "1");
    },
  },
  methods: {
    //修改购物车中某一个商品的数量 throttle 节流控制用户点击操作过快导致商品数量小于1
    handler: throttle(async function (type, disNum, cart) {
      //用户可以通过＋ - 和直接修改输入框的值来修改购物车中商品的数量
      switch (type) {
        case "add":
          disNum = 1;
          break;
        case "minus":
          disNum = cart.skuNum <= 1 ? 0 : -1;
          break;
        case "change":
          // isNaN判断用户输入是否包含除数字以外的
          if (isNaN(disNum) || disNum < 1) {
            disNum = 0;
            break;
          } else {
            //取整是因为可能用户输入小数
            disNum = parseInt(disNum) - cart.skuNum;
            break;
          }
      }
      try {
        //成功
        await this.$store.dispatch("addOrUpdateShopCart", {
          skuId: cart.skuId,
          skuNum: disNum,
        });
        this.$store.dispatch("getShopCart");
      } catch (error) {}
    }, 500),
    //删除购物车中某一个商品
    deleteCartById: throttle(async function (skuId) {
      if (confirm("你确定要删除该商品吗？")) {
        try {
          await this.$store.dispatch("deleteCartById", { skuId: skuId });
          this.$store.dispatch("getShopCart");
        } catch (error) {
          alert("服务器错误，删除失败，清稍后重试!");
        }
      }
    }, 1000),
    //修改每个商品是否选中状态
    async updateStateById(cart, event) {
      let isChecked = event.target.checked ? 1 : 0;
      try {
        await this.$store.dispatch("updateStateById", {
          skuId: cart.skuId,
          isChecked: isChecked,
        });
        this.$store.dispatch("getShopCart");
      } catch (error) {}
    },
    //删除全部选中的购物车中的商品
    async deleteAllCheckedCart() {
      //过滤购物车中 选中的商品
      let selectGoods = this.cartInfoList.filter((_d) => _d.isChecked == "1");
      let _this = this;
      //遍历删除所有选中的商品
      await selectGoods.forEach(function (item, index) {
        //调用通过购物车中商品id删除购物车中商品的接口
        _this.$store.dispatch("deleteCartById", { skuId: item.skuId });
        //重新获取购物车数据渲染页面
        _this.$store.dispatch("getShopCart");
      });
    },
    async updateAllCartChecked(event) {
      try {
        let isChecked = event.target.checked ? "1" : "0";
        await this.$store.dispatch("updateAllCartIsChecked", isChecked);
        this.$store.dispatch("getShopCart");
      } catch (error) {
        alert(error.message);
      }
    },
    //结算路由跳转
    settle(){
      this.$router.push('trade')
    }
  },
};
</script>

<style lang="less" scoped>
.cart {
  width: 1200px;
  margin: 0 auto;

  h4 {
    margin: 9px 0;
    font-size: 14px;
    line-height: 21px;
  }

  .cart-main {
    .cart-th {
      background: #f5f5f5;
      border: 1px solid #ddd;
      padding: 10px;
      overflow: hidden;

      & > div {
        float: left;
      }

      .cart-th1 {
        width: 25%;

        input {
          vertical-align: middle;
        }

        span {
          vertical-align: middle;
        }
      }

      .cart-th2 {
        width: 25%;
      }

      .cart-th3,
      .cart-th4,
      .cart-th5,
      .cart-th6 {
        width: 12.5%;
      }
    }

    .cart-body {
      margin: 15px 0;
      border: 1px solid #ddd;

      .cart-list {
        padding: 10px;
        border-bottom: 1px solid #ddd;
        overflow: hidden;

        & > li {
          float: left;
        }

        .cart-list-con1 {
          width: 15%;
        }

        .cart-list-con2 {
          width: 35%;

          img {
            width: 82px;
            height: 82px;
            float: left;
          }

          .item-msg {
            float: left;
            width: 150px;
            margin: 0 10px;
            line-height: 18px;
          }
        }

        .cart-list-con4 {
          width: 10%;
        }

        .cart-list-con5 {
          width: 16%;

          .mins {
            border: 1px solid #ddd;
            border-right: 0;
            float: left;
            color: #666;
            width: 6px;
            text-align: center;
            padding: 8px;
          }

          input {
            border: 1px solid #ddd;
            width: 40px;
            height: 33px;
            float: left;
            text-align: center;
            font-size: 14px;
          }

          .plus {
            border: 1px solid #ddd;
            border-left: 0;
            float: left;
            color: #666;
            width: 6px;
            text-align: center;
            padding: 8px;
          }
        }

        .cart-list-con6 {
          width: 11%;

          .sum {
            font-size: 16px;
          }
        }

        .cart-list-con7 {
          width: 13%;

          a {
            color: #666;
          }
        }
      }
    }
  }

  .cart-tool {
    overflow: hidden;
    border: 1px solid #ddd;

    .select-all {
      padding: 10px;
      overflow: hidden;
      float: left;

      span {
        vertical-align: middle;
      }

      input {
        vertical-align: middle;
      }
    }

    .option {
      padding: 10px;
      overflow: hidden;
      float: left;

      a {
        float: left;
        padding: 0 10px;
        color: #666;
      }
    }

    .money-box {
      float: right;

      .chosed {
        line-height: 26px;
        float: left;
        padding: 0 10px;
      }

      .sumprice {
        width: 200px;
        line-height: 22px;
        float: left;
        padding: 0 10px;

        .summoney {
          color: #c81623;
          font-size: 16px;
        }
      }

      .sumbtn {
        float: right;

        a {
          display: block;
          position: relative;
          width: 96px;
          height: 52px;
          line-height: 52px;
          color: #fff;
          text-align: center;
          font-size: 18px;
          font-family: "Microsoft YaHei";
          background: #e1251b;
          overflow: hidden;
        }
      }
    }
  }
}
</style>